Chef Polo Dobkin’s proud father dragged me to Williamsburg, kicking and grumbling, for dinner at DuMont, casual, cheap, and very young. Tucking into the hearty portions of lamb ragout with gnocchi, braised short ribs, and thick-sliced duck breast with a poblano tamale and celery has made me a commuter. I’ve already been back with pals, pleased to share grilled endive and radicchio with goat cheese, luscious gingered tuna tartare, the special grilled leg of lamb, and . . . impossible to resist, the mac-and-cheese, a creamy and crusted swamp studded with radiatore pasta. At its launch, DuMont (named for a sign that owner Colin Devlin found a block away) was a laid-back burger joint, until Dobkin and co-chef Cal Elliot (formerly of the Dining Room in Manhattan) came on with new ambition. The cheese plate shows how serious they are. My gripes are an occasional over-reduced sauce, and having to wait in line for a table with the neighborhood swarm that quickly fills the tiny bar. Once it gets balmy, the garden will double the space.